Certain solid state electrochemical cells such as high temperature rechargeable lithium electrochemical cells are known that use a solid solution of lithium germanium oxide (Li.sub.4 GeO.sub.4) and lithium vanadium oxide (Li.sub.3 VO.sub.4) as the lithium ion conducting solid electrolyte. The solid electrolyte can be represented by the general formula Li.sub.3+x Ge.sub.x V.sub.1-x O.sub.4 where x is a value from 0 to 1. The conductivity of the solid solution, Li.sub.3.6 Ge.sub.0.6 V.sub.0.4 O.sub.4 is about 0.08 S/cm at 300.degree. C. and the solid solution has been used as a lithium ion conducting solid electrolyte for solid state cells. However, these high conductivities are achieved with sintered pellets of the solid electrolyte that are difficult to fabricate. The conductivities of the easily fabricated pressed pellets of the solid electrolyte are much smaller than the conductivities of the sintered pellets so that the cells fabricated with pressed pellets of the solid electrolyte do not deliver the high discharge rates required for pulse power applications.
The use of these lithium ion conducting solid electrolytes has also been suggested for other electrochemical cells as for example, high temperature thermal cells. These cells are required for applications in fuses, projectile rockets, bombs, missiles, decoys, jammers and torpedoes. However, in this case too, cells fabricated with pressed pellets of the solid electrolyte do not deliver the required high discharge rates.